A multimedia computer system that converts an input RGB signal to a luminance signal and a color difference signal, extracts a characteristic point of the luminance signal for each frame, corrects the luminance signal and the color difference signal and displays images has been proposed in the past (refer to JP-A-2002-132225, page 4 and FIG. 1, for example).
When this system is applied to a mobile terminal device operated by a battery, consumed power increases as the luminance signal and the color difference signal are corrected for each frame. There is often the case where an operator is away from home and cannot charge the mobile terminal device. When consumed power is great, the usable time of the mobile terminal becomes short and the ease of use or usability of the device is lost. Therefore, the mobile terminal device that can display satisfactory images at low power of consumption has been required. Another problem is that when environmental light is incident into the display, the image becomes difficult to watch and the mobile terminal device cannot be conveniently used outdoors.
Therefore, an image processing apparatus and a mobile terminal device having improved ease of use for users have been required.